An original method based on metal-free ligand and lanthanide acetate direct interaction in the presence of a strong organic base (DBU) is used to prepare sandwich-type gadolinium and ytterbium crown-ether substituted phthalocyanines bis[4,5,4′,5′,4″,5″,4‴,5‴-tetrakis(1,4,7,10,13-pentaoxatridecamethylene)phthalocyaninato]gadolinium (ytterbium) and tris[4,5,4′,5′,4″,5″,4‴-,5‴-tetrakis(1,4,7,10,13-pentaoxatridecamethylene)phthalocyaninato]digadolinium (ytterbium) which are characterized by MALDI-TOF mass spectrometry and UV-vis spectroscopy.

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The employment of trans-[PtCl(OH)(NH 3 ) 2 ]´H 2 O as the platinum source offers a convenient and efficient way to prepare 1:1 adducts with the model nucleobases 9-methyladenine (9-MeAde) and 9-methylhypoxanthine (9-MeHypH). The resulting complexes, trans-[PtCl(NH 3 ) 2 (9-MeAde-N7)]ClO 4 and trans-[PtCl(NH 3 ) 2 (9-MeHyp-N7)]2 H 2 O, were structurally characterized by X-ray crystallography. The crystal packing of both complexes is stabilized by a hydrogen-bonding network involving primarily NH 3 ligands and perchlorate oxygens in trans-[PtCl(NH 3 ) 2 -(9-MeAde-N7)]ClO 4 , and NH 3 ligands and the C(6)O group of the nucleobase in trans-[PtCl(NH 3 ) 2 (9-MeHyp-N7)]2 H 2 O. Three hydrogen bonds to the oxo group in the latter compound suggest that the negative charge caused by N1H deprotonation of the nucleobase is partly located on the oxygen atom; this is supported by the slightly larger downfield shift of C(6) over C(2) in the 13 C spectrum. However, the anticipated lengthening of the C(6)ÀO(6) bond upon N1H deprotonation was not verified by X-ray results. Kinetics for the Cl À hydrolysis in basic aqueous solution were followed by 195 Pt NMR and HPLC analysis, which showed the formation of only one product in both cases with a 195Pt chemical shift typical for a PtN 3 O coordination sphere. The comparable kinetic data found by these two methods reveal that the water molecule acts as the nucleophile in the hydrolysis reactions and that it displaces the Cl À ligand more readily in the 9-methyladenine complex.

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Chemie, Information und Computer, diese drei Schlagworte verknüpfen das Know‐how von Computerexperten mit dem der Chemiker. Wo sind die zukunftsträchtigen Themen? Welche Vorteile Ziehen Chemiker aus der Kombination?